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Same-Game Parlay Calculator

Built by Kevin Glover · @gloverbuilds · Verified formula

Calculate SGP payouts for correlated and uncorrelated prop combinations. See how correlation affects true odds.

📅 Updated April 2026 ✅ Formula verified 📖 4 min read 🆓 Free · No sign-up

In this article

Why Sportsbooks Love SGPs
Using Correlation to Your Advantage

Why Sportsbooks Love SGPs

Same-game parlays are the most profitable product for sportsbooks. The house edge on a typical 3-leg SGP is 15-25% compared to 4-5% on a straight bet. Sportsbooks achieve this by treating correlated events as independent when pricing legs. If you parlay a QB over passing yards with the game over, these are positively correlated — but the SGP prices them as if they were independent, overcharging you.

Using Correlation to Your Advantage

The best SGP strategy is to identify strongly correlated legs that the sportsbook underprices. Examples: team to win + player from that team to score a touchdown, or game over + specific QB to throw 2+ TDs. The sportsbook treats these legs as less correlated than they truly are, occasionally creating +EV opportunities within the SGP format.

⚡ CalcWolf Insight

A Harvard study of DraftKings SGP data found the average house edge was 19.7% — nearly 4x the edge on standard spread bets. The most profitable SGPs for the sportsbook were those with 4+ legs, where the compounding margin effect is strongest.

Frequently asked questions

Are same-game parlays worth it?▾

For entertainment: yes, they offer big payouts from small stakes. For profit: rarely. The typical SGP has a 15-25% house edge. However, if you can identify strongly correlated legs that the sportsbook misprices, occasional +EV SGPs do exist. Most sharps avoid SGPs except for these rare correlation plays.

How do sportsbooks price SGPs?▾

Sportsbooks use proprietary correlation models to adjust leg odds within an SGP. However, these models are imperfect — they sometimes over-adjust (making negatively correlated combinations too expensive) and sometimes under-adjust (making positively correlated combinations too cheap). Finding the under-adjustments is the key to profitable SGP betting.

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Kevin Glover · @gloverbuilds

Founder, CalcWolf · GLVTS · Blickr

All formulas sourced from primary references — IRS publications, peer-reviewed research, and official standards. Results are tested against independent reference calculators before publishing. Rates and brackets updated when official sources change. Editorial policy →